Butyl rubber insulation

Brands

DynaMat Extreme (not the standard DynaMat, which is an asphalt product)

Second Skin Damplifier and Damplifier Pro

Info

There’s a lot of good info on butyl insulation at the sounddeadenershowdown page, so I’ll send you there instead of repeating it. It’s a great site with a lot of good information, mostly relating to acoustic insulation.

I’m having a hard time tracking down information on butyl outgassing, and what little I can find points to it releasing toxic vapors. Not sure to what degree, but for now I’m going to avoid it. Too bad, because it’s a great, dense, acoustic insulation with thermal insulative qualities as well. With a foil backing to reflect radiant heat, it would provide a thin, fairly effective barrier. I don’t believe it would compete on a thermal insulation base with many of the other options, but if your intention is moisture control and sound insulation, it might be a good choice. Can also be purchased with an adhesive backing, making application a breeze.